Motion Flashcards
Define displacement; vector or scalar?
Distance traveled in a given direction
Vector quantity
s=vt
Define velocity
Rate of change in displacement
v=s/t
Defined acceleration
Rate of change in velocity
a=v/t
Displacement-time graph;
Straight horizontal line
Stationary object
Displacement-time graph;
Constant non-zero gradient
Constant velocity
Displacement-time graph;
Curved line
Acceleration (gradient increases)
Deceleration (gradient decreases)
Velocity-time graph;
Straight horizontal line
Constant velocity
Velocity-time graph;
Constant non-zero line
Accelerating/decelerating
Velocity-time graph;
Area under curve
Displacement
Acceleration-time graph;
Area
Velocity
Define ‘g’
Free fall acceleration, 9.81ms^-2
Why is horizontal acceleration 0 for projectile motion
· No horizontal forces acting upon projectiles => horizontal velocity of a projectile is constant
· Only force which acts on a projectile is gravitational force (vertically downwards)
Stopping distance
Thinking + braking distance
Thinking distance
· Distance traveled between when object is spotted and when driver applies brake
· Initial speed,u * reaction time
Braking distance
· Distance between when driver applies brake and car stops
· Proportionate to u^2 (all KE must be dissipated
